Preparation And Performance Of Composite Mesoporous Carbon Membranes

Carbon membranes are a type of membrane materials obtained by pyrolysis materials with carbon element at high temperature. They can be potentially used in different gas separation, purification and membrane reactors owing to their many advantages such as the superior chemical, thermal stability, excellent capacity to endure high temperature and pressure and electrical conductivity. Carbon membranes mainly include homogeneous carbon membranes and composite carbon membranes according to the structure difference. The low mechanical strength of the homogeneous carbon membranes limit their wide utilization in gas separation and the study of composite carbon membranes started to solve this problem. Composite carbon membranes are a kind of membranes which could be prepared by coating precursor on supports to improve mechanical strength effectively. However, it is hard to prepare consecutive and flawless composite carbon membranes when the macropore coal-based carbon membranes are used as supports because of their pin-holes and flaws. Mesoporous carbon membranes have been attracting considerable attention because of their pore uniform and advanced porosity. Due to the characteristic of the mesoporous carbon membranes, they could be used as a very good membrane support. However the mesoporous carbon membranes prepared in this stage are brittle and easily fragile, which limit the application of being supports.Ordered mesoporous carbon materials are a type of new functional materials with high surface area and uniform pore distribution. More recently, the soft template method becomes a popular method to prepare ordered mesoporous carbon materials, which directly derived from organic-organic composites by self-assembly of block copolymers, and get the mesoporous carbons by pyrolysis the block copolymers. Different pore structures of mesoporous carbons have been prepared successfully by now.Herein, in order to solve both the problem of coal supports’pin-holes and flaws and the disadvantages of easily fragile with homogeneous mesoporous carbon membranes, we firstly use the block copolymer F127(EO106PO70EO106) as the soft template, self-assembling with the precursor prepared by phenol/resorcinol and formaldehyde react in different conditions to get ordered mesoporous carbon materials, and investigate the influence matters in the process.After then, using the coal brand carbon membrane as the support which investigates the influence of balling milling the coal raw materials, we impregnation the supports by mesoporous polymers with different concentrations and pyrolysis the block copolymer in the mesoporous polymer to get the mesoporous pores. The mesoporous layer on the supports is successfully put in by the method of spinning coating and dipping coating. Besides, the influence effects such as polymer concentrations and mesoporous coating mass are discussed. The results indicate that the gas separation properties are related to the mesoporous structure on the supports, and the permeability results are worm structure> p6mm> Im3m, and O2permeation rate of the mesoporous composite carbon membranes with p6mm structure is up to8276GPU, and the selectivities of O2/N2of mesoporous composite carbon membranes with Im3m structure is up to1.17.